I got the car running on Megasquirt II today. Right now it's only running fuel. I haven't wired up the IAT sensor or any O2 sensors yet. It dosn't run great, but I'm sure it will run better when it's all tuned out with all the sensors hooked up. One problem though. Wait for it....

It's overheating. My cooling fans are not coming on. I guess I'll double check my wiring harness, but the ONLY wires I cut from my patch harness were four wires to the fuel injectors. Any thoughts or do I have to do anything special for the cooling fans to work? Like I said, I didn't cut the fan wires, only the injector wires.

Yea, I'm running those schematics you posted arga. I'm having an overheating problem though. I'm going to verify the fans are not coming on, though I'm fairly sure they are not, and that's the problem. will check fuses too.

hold up. You are running the MS with factory sensors? No having to retrofit pre 99 parts?

AbeFM and arga helped me out with it. With Abe's circuits, I never could get it to run right. However, I'm running mine in Parallel with the stock ecu, and he's running standalone. Arga and I are running in Parallel. Yea, if your running MS II in parallel it's simple and easy to make circuits to read the stock sensors. If your running it standalone, talke to AbeFM, as he has the circuits that work for running it standalone.

I'm still having goofy temp readings on MT though. I'm gonna reset my CLT values per arga's table above and see what happens. I have a GM open element IAT sensor so I left those values alone. Oddly though, I get a 170 degree reading on the IAT guage in MT with or without the sensor hooked up and it never changes. Don't know what could be causing that. Any thoughts?

I've heard that some people remove resistor R7 on there ms, and it can affect these sensor values. Anyone know much about that? The coolant temp in MT works fine on the stim, but not in the car, with or without a sensor hooked up.

Edit: I hooked up the fans to MS II so I now have control of the them. Howeve, I'm getting goofy temp readings in MS so I'll have to figure that out. Hopefully arga's vaulues for the CLT calibration will fix these issues. Not sure about what's causing teh IAT issues. I got my LC-1, so I'm gonna install it shortly.

Are the numbers for temp on the left in degrees C or F? I just measured the resistance of my CLT sensor at 1400 ohms between sensor out (2E) and ground. That's with my jumper harness pluged into the cars harness, but not into the factory ecu. power was off.

It's currently 41.5 degrees 10 feet from my car, and I have not run the car in 10 hours. I'm trying to get an accurate clt temp guage reading on MT.

Guys, do I need a diff VE table for fuel? I show 45kpa when idling, and if i pinch the vacuum line to the map sensor, I can make it go up to say 50, and it will idle smoothly. I let go, it goes back to running poorly.

My GM open element AIT sensor refuses to change values. I double checked my wiring, and I have one side of the sensor going to +5V, and the other going to MS. Strangely, I can measure 5V at BOTH leads where the sensor plugs into. Should I switch the +5V that goes into that sensor to ground perhaps?

An IAT reading of 170 will make your car run horrible. It's like when you get really bad IAT heatsoak. If you tune your idle at like 70* you'll have to use IAT enrichment to make it idle once the sensor heat soaks. For example, while idling my sensor will heatsoak from 70 up to 110-120 or so. The IAT enrichment is disabled by the time i get to 1700 rpm or so.

You can use aluminum to make your heatsink maybe use two pieces stacked so it looks like it has a upper and lower just to get that extra heat extraction.
Copper sheet isn't cheap or easy to get in small pieces that i know of.

Quote:

Originally Posted by arga

Temps are in F. I'm using the default MS resistors. I'm using the stock temp sensors, though.

What are you using for your bias resistance values? Im using 1544 and it seems to work great but i have R7 removed. So i would figure you'd be using something ~4k or so but due to recent events with paul's testing that's not how things work for some reason.

I cut a 1" copper pipe coulpler down it's length, hammered it flat, and dremeled a 3/4" hole in it. If someone tells you to cut a hole in copper with a dremel or they're gonna shoot you, take the bullet. It tooke 30 minutes of dremeling to get it, and I burned up something in my dremel. It let some smoke out and has 1/2 the power. Hopefully just the brushes, but I don't know.